Reports of major ectodermal dysplasias have been sufficiently infrequent in medical literature to warrant a brief review and the description of an unreported case involving hair, teeth and skin. The condition in this small group of cases, less than thirty in number, has been designated by Weech1 as the anhidrotic type of hereditary ectodermal dysplasia because of the inability of the patients to perspire and because of the part played by inheritance. Most writers have eliminated syphilis and chemical injury (Jesionek2) during embryonic life as etiologic factors, and have attempted to explain the occurrence of this unusual condition on the basis of endocrine disturbances and heredity.

REVIEW OF THE LITERATURECredit for the earliest description of this type of case seems to belong to Thurnam,3 who, in 1848, described a case in a man, aged 58 years, who showed typical symptoms. An autopsy on this patient was